transparent aluminum (thing)

Before the purists jump on me, no, technically it isn't a metal. It's better. It's a ceramic. However, it's nothing more than carefully-treated and maybe doped aluminum oxide (Al2O3,Professor Pi informs me. Thanks!). It is, however, still aluminum, even if not in the 'pure' form.It's under this title because this is how they're referring to it in the press.

German materials science gurus at the Fraunhofer Institute for Ceramics Technologies (I believe) announced the week of 2/11/02 that they have successfully manufactured transparent aluminum (or aluminium for the rest of the world) tiles. The tiles are made, in the roughest possible description, by taking microfine particles of aluminum oxide* and baking them at around 1200 degrees Celsius during a fairly tightly-controlled process. The end result is a transparent but slightly white-tinted (milky) substance. The announcement press release showed a photo of a hand lighting a candle with a match behind a tile of the stuff; everything was clearly visible, and the colors were slightly paler but easily recognizable.

There was a story on Slashdot, you can search there if you need confirmation. It will point you to the following Der Spiegel article:

The characteristics of the material are such, the team reported, that a 1-cm thick tile (not-so-coincidentally, the thickness required by Chief Engineer Montgomery Scott in Star Trek IV: The Voyage Home) would have a tensile strength or pressure rating approximately three times as great as an equivalent thickness of steel plate, and would weigh around 1/3 as much.

I just love it when reality takes its cues from science fiction; you can't tell me at least a few of those working on this hadn't first been tickled by the Star Trek mention of the stuff. Of course, Star Trek can't have everything; Germany sure ain't San Francisco, which is where Scott and McCoy handed over the formula to an American firm.

Glass armor, although it sounds oxymoronic, is necessary for use in direct vision ports ("vision blocks") of armored vehicles. The new material, although more expensive to produce, resists damage from larger and more energetic projectiles and hence should require replacement less often - as well as (more importantly) offering better protection to vehicle occupants. For more information on this application, see: